Thread: Why does the gyro need the ADC?
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Unread 25-10-2006, 22:33
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Re: Why does the gyro need the ADC?
The gyro puts out a voltage, typically from 0 to 5 volts indicating the rate of rotation of the sensor along its sensing axis. When it's not moving the output ideally rests at 2.5 volts (no positive or negative rotation speed) and when it goes in one direction the voltage goes down and in the other it goes up. Since computers are digital they can only sense if the voltages is greater then about 4 volts (binary 1) or less than about 1.2 volts (binary 0) (Those numbers are fuzzy blurbs of memory, might be a bit off). The ADC converts that value to a number in the code, from 0 (0v) to 1023 (5v) for use in the integration calculations (For more info about integrating see the numerous whitepapers on gyro and PID use.)
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